Here’s a fine comment from John Wesley on Christian unity. By ‘catholic spirit’, Wesley meant what we today would call an ‘inclusive’ attitude towards Christians of other ‘traditions’. By ‘speculative latitudinarianism’, he meant doctrinal indifference. So to the quote:-
A catholic spirit is not speculative latitudinarianism. It is not an indifference to all opinions: this is the spawn of hell, not the offspring of heaven. This unsettledness of thought, this being “driven to and fro, and tossed about with every wind of doctrine,” is a great curse, not a blessing; an irreconcilable enemy, not a friend, to true catholicism. A man of a truly catholic spirit has not now his religion to seek. He is fixed as the sun in his judgement concerning the main branches of Christian doctrine…Observe this, you who know not what spirit ye are of: who call yourselves men of a catholic spirit, only because you are of a muddy understanding; because your mind is all in a mist; because you have no settled, consistent principles, but are for jumbling all opinions together. Be convinced, that you have quite missed your way; you know not where you are…Go, first, and learn the first elements of the gospel of Christ, and then shall you learn to be of a truly catholic spirit.
(Wesley, Forty-Four Sermons, 453)